Which property did Medeleev use to classify the elements in his periodic table? Did he stick to that?

Explanation

Mendeleev classified the elements on the basis of their increasing atomic weights in the periodic table. He arranged almost 63 elements in order of their increasing atmic weights placing together elements with similar properties in a vertical column. He observed that while classifying elements in the periodic table according to increasing atomic weight, there were certain elements which had different properties than those elements belonging to the same group. for such cases, mendeleev prioritised the properties of the element over its atomic weight. so, he placed an element with higher atomic weight. so, he placed an element with higher atomic weight before an element with lower atomic weight. for example, iodine [I (126.91)] with lower atomic weight than tellurium [Te (127.61)] is placed after tellurium in group VII along with elements like fluroine. chlorine etc., due to similarities in properties with these elements. thus, mendeleev did not stick to his idea of classifying lements only according to the increasing atomic weights.